This specification relates to azimuthally-selective downhole nuclear magnetic resonance (NMR) tools, for example, for obtaining NMR data from a subterranean region.
In the field of logging (e.g. wireline logging, logging while drilling (LWD) and measurement while drilling (MWD)), nuclear magnetic resonance (NMR) tools have been used to explore the subsurface based on the magnetic interactions with subsurface material. Some downhole NMR tools include a magnet assembly that produces a static magnetic field, and a coil assembly that generates radio frequency (RF) control signals and detects magnetic resonance phenomena in the subsurface material. Properties of the subsurface material can be identified from the detected phenomena.
Like reference symbols in the various drawings indicate like elements.